KNX remove custom deprecation warnings

[farmio]

Proposed change

• use cv.deprecated instead of custom deprecation warnings with links to external sites

This is a follow-up for #46874 (comment)

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

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• This PR fixes or closes issue: fixes #
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[probot-home-assistant]

Hey there @Julius2342, @marvin-w, mind taking a look at this pull request as its been labeled with an integration (knx) you are listed as a codeowner for? Thanks!
_{^{(message by CodeOwnersMention)}}

[MartinHjelmare]

Please start on a fresh branch based on latest dev.

[farmio]

Did a reset and cherry-pick.

[MartinHjelmare]

Thanks!